An agricultural tractor is conventionally provided with a travel machine body to which an engine and a transmission case are mounted, a lift arm which is arranged in an upper surface side of a rear portion of the transmission case so as to freely oscillate up and down, and an elevating hydraulic cylinder which oscillates up and down the lift arm, and the elevating hydraulic cylinder for driving the lift arm is outward installed to the rear side of the transmission case (refer, for example, to patent document 1).